Sun Sheng, Zhang Hanwen, Wang Qiang, Zhu Danjiang, Wen Yuwei
Department of Orthopaedics, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China.
Sci Rep. 2025 Mar 10;15(1):8232. doi: 10.1038/s41598-025-93172-5.
Segmental long bone defects present a significant clinical challenge as critical-size defects cannot heal spontaneously. Most studies focus on adult bone defects, with limited research on pediatric cases. To enhance the study of bone defects in children, we established a juvenile sheep bone defect model. Juvenile small-tailed Han sheep were used to create a 2 cm tibial bone defect, stabilized with a plate and screws. Tissue-engineered bone scaffolds were implanted at the defect site, and the limb was immobilized with a plaster cast for 3 months. Sheep were euthanized at 3 and 6 months post-surgery, and tibiae were examined using X-ray, microCT, and histological staining. Tibial defect models were established in 7 sheep, with 2 euthanized at 3 months and 5 at 6 months. X-ray revealed cortical bridging. MicroCT and histological staining showed new bone distribution, with the 6-month group demonstrating increased bone formation and bridging at the scaffold center. There was no significant difference in longitudinal growth rates between the operated and contralateral tibiae. We developed a reproducible model for juvenile tibial segmental defects in sheep, providing a robust basis for studying pediatric long bone segmental defects.
节段性长骨缺损是一项重大的临床挑战，因为临界尺寸的缺损无法自发愈合。大多数研究聚焦于成人骨缺损，对儿科病例的研究有限。为加强对儿童骨缺损的研究，我们建立了幼年绵羊骨缺损模型。使用幼年小尾寒羊制造一个2厘米的胫骨骨缺损，用钢板和螺钉固定。将组织工程骨支架植入缺损部位，并用石膏固定肢体3个月。在术后3个月和6个月对绵羊实施安乐死，并使用X射线、显微CT和组织学染色检查胫骨。在7只绵羊中建立了胫骨缺损模型，其中2只在3个月时实施安乐死，5只在6个月时实施安乐死。X射线显示皮质桥接。显微CT和组织学染色显示了新骨分布，6个月组在支架中心显示出骨形成增加和桥接。手术侧胫骨与对侧胫骨的纵向生长速率没有显著差异。我们开发了一种可重复的幼年绵羊胫骨节段性缺损模型，为研究儿科长骨节段性缺损提供了有力基础。
